Does Impaired Plantar Cutaneous Vibration Perception Contribute to Axial Motor Symptoms in Parkinson's Disease? Effects of Medication and Subthalamic Nucleus Deep Brain Stimulation.

OBJECTIVE: To investigate whether impaired plantar cutaneous vibration perception contributes to axial motor symptoms in Parkinson's disease (PD) and whether anti-parkinsonian medication and subthalamic nucleus deep brain stimulation (STN-DBS) show different effects. METHODS: Three groups were evaluated: PD patients in the medication "on" state (PD-MED), PD patients in the medication "on" state and additionally "on" STN-DBS (PD-MED-DBS), as well as healthy subjects (HS) as reference. Motor performance was analyzed using a pressure distribution platform. Plantar cutaneous vibration perception thresholds (VPT) were investigated using a customized vibration exciter at 30 Hz. RESULTS: Motor performance of PD-MED and PD-MED-DBS was characterized by greater postural sway, smaller limits of stability ranges, and slower gait due to shorter strides, fewer steps per minute, and broader stride widths compared to HS. Comparing patient groups, PD-MED-DBS showed better overall motor performance than PD-MED, particularly for the functional limits of stability and gait. VPTs were significantly higher for PD-MED compared to those of HS, which suggests impaired plantar cutaneous vibration perception in PD. However, PD-MED-DBS showed less impaired cutaneous vibration perception than PD-MED. CONCLUSIONS: PD patients suffer from poor motor performance compared to healthy subjects. Anti-parkinsonian medication in tandem with STN-DBS seems to be superior for normalizing axial motor symptoms compared to medication alone. Plantar cutaneous vibration perception is impaired in PD patients, whereas anti-parkinsonian medication together with STN-DBS is superior for normalizing tactile cutaneous perception compared to medication alone. Consequently, based on our results and the findings of the literature, impaired plantar cutaneous vibration perception might contribute to axial motor symptoms in PD.

Anticipatory Postural Adjustments and Compensatory Postural Responses to Multidirectional Perturbations-Effects of Medication and Subthalamic Nucleus Deep Brain Stimulation in Parkinson's Disease.

BACKGROUND: Postural instability is one of the most restricting motor symptoms for patients with Parkinson's disease (PD). While medication therapy only shows minor effects, it is still unclear whether medication in conjunction with deep brain stimulation (DBS) of the subthalamic nucleus (STN) improves postural stability. Hence, the aim of this study was to investigate whether PD patients treated with medication in conjunction with STN-DBS have superior postural control compared to patients treated with medication alone. METHODS: Three study groups were tested: PD patients on medication (PD-MED), PD patients on medication and on STN-DBS (PD-MED-DBS), and healthy elderly subjects (HS) as a reference. Postural performance, including anticipatory postural adjustments (APA) prior to perturbation onset and compensatory postural responses (CPR) following multidirectional horizontal perturbations, was analyzed using force plate and electromyography data. RESULTS: Regardless of the treatment condition, both patient groups showed inadequate APA and CPR with early and pronounced antagonistic muscle co-contractions compared to healthy elderly subjects. Comparing the treatment conditions, study group PD-MED-DBS only showed minor advantages over group PD-MED. In particular, group PD-MED-DBS showed faster postural reflexes and tended to have more physiological co-contraction ratios. CONCLUSION: medication in conjunction with STN-DBS may have positive effects on the timing and amplitude of postural control.

Opicapone Use in Clinical Practice across Germany: A Sub-Analysis of the OPTIPARK Study in Parkinson's Disease Patients with Motor Fluctuations.

INTRODUCTION: The OPTIPARK study confirmed the effectiveness and safety of opicapone as adjunct therapy to levodopa in patients with Parkinson's disease (PD) and motor fluctuations under real-world conditions. The aim of this sub-analysis was to evaluate opicapone in the German patient cohort of OPTIPARK in order to provide country-specific data. METHODS: OPTIPARK was an open-label, single-arm study conducted in routine clinical practice across Germany and the UK. Patients with PD and motor fluctuations received once-daily opicapone 50 mg for 3 months in addition to levodopa. The primary endpoint was Clinicians' Global Impression of Change (CGI-C). Secondary assessments included Patients' Global Impressions of Change (PGI-C), Unified Parkinson's Disease Rating Scale (UPDRS) I-IV, Parkinson's Disease Questionnaire (PDQ-8), and Non-Motor Symptoms Scale (NMSS). This sub-analysis reports outcomes from the German patients only. RESULTS: Overall, 363 (97.6%) of the 372 patients included in the German cohort received ≥1 dose of opicapone and 291 (80.2%) completed the study. Improvements on CGI-C and PGI-C were reported by 70.8% and 76.3% of patients, respectively. UPDRS scores improved for activities of daily living during OFF time by -3.3 ± 4.5 points and motor scores during ON time by -5.3 ± 7.9 points. PDQ-8 and NMSS scores also demonstrated improvements. Treatment emergent adverse events considered at least possibly related to opicapone occurred in 37.7% of patients, with most being of mild or moderate intensity. CONCLUSION: Opicapone added to levodopa in patients with PD and motor fluctuations was effective and generally well tolerated in routine clinical practice across Germany.

Sex Disparities in the Self-Evaluation of Subthalamic Deep Brain Stimulation Effects on Mood and Personality in Parkinson's Disease Patients.

Changes in personality are one of the main concerns Parkinson's disease (PD) patients raise when facing the decision to undergo neurosurgery for deep brain stimulation (DBS) of the subthalamic nucleus (STN). While clinical instruments for monitoring functional changes following DBS surgery are well-established in the daily therapeutic routine, personality issues are far less systematically encompassed. Moreover, while sex disparities in the outcomes of STN-DBS therapy have been reported, little is known about the different effects that DBS treatment may have on mood and personality traits in female and male patients. To this aim, the effect of STN-DBS on personality traits was assessed in 46 PD patients (12 women and 34 men) by means of the Freiburg Personality Inventory. The Becks Depression Inventory (BDI-I) and the Parkinson's Disease Questionnaire were used to evaluate patients' level of depression and quality of life (QoL). Patients completed the questionnaires a few days before, within the first year, and 2 years after surgery. The 12 personality traits defined by the FPI-R questionnaire did not change significantly after STN-DBS surgery (p = 0.198). Women declared higher depression scores through all study stages (p = 0.009), but also showed a stronger QoL amelioration after surgery than male patients (p = 0.022). The BDI-I scores of female patients clearly correlated with their levodopa equivalent daily dose (LEDD; r = 0.621, p = 0.008). Remarkably, in both male and female patients, higher pre-operative LEDDs were related to worse post-operative QoL scores (p = 0.034). These results mitigate the concerns about systematic personality changes due to STN-DBS treatment in PD patients and encourage an early DBS approach, before severe levodopa-induced sequelae may irreparably compromise the patients' QoL. In the future, more focus should lie on sex-related effects, since female patients seem to profit more than male patients from STN-DBS, in terms of reduced depressive symptoms associated with a reduction of the LEDD and amelioration of QoL. These aspects may help to redress the sex imbalance in PD patients treated with DBS, given that women are still strongly under-represented.

Long-term incobotulinumtoxinA treatment for chronic sialorrhea: Efficacy and safety over 64 weeks.

BACKGROUND: Botulinum neurotoxin (BoNT) is an effective treatment for chronic sialorrhea; however, reliable and robust evidence supporting long-term efficacy and safety is lacking. This study investigated the efficacy and safety of repeated incobotulinumtoxinA injections for chronic sialorrhea over 64 weeks. METHODS: Adults with sialorrhea were randomized (2:2:1) to incobotulinumtoxinA 75 U, incobotulinumtoxinA 100 U (n = 74 each), or placebo (n = 36) in the double-blind, placebo-controlled main period (NCT02091739). Eligible subjects entered the extension period and received dose-blinded incobotulinumtoxinA 75 or 100 U in three further 16±2-week injection cycles. Efficacy and safety assessments in subjects who received incobotulinumtoxinA throughout the study included unstimulated salivary flow rate (uSFR), subjects' Global Impression of Change Scale (GICS), Drooling Severity and Frequency Scale (DSFS), modified Radboud Oral Motor Inventory for Parkinson's Disease (mROMP) drooling, speech, and swallowing symptom scores, and incidence of adverse events (AEs). RESULTS: In total, 173/184 subjects (94%) completed the main period and entered the extension period; 141 subjects received incobotulinumtoxinA 75 U (n = 69) or 100 U (n = 72) in both periods. Mean uSFR decreased consistently with repeated incobotulinumtoxinA 75 and 100 U treatment and by -0.16 and -0.17, respectively, at the end-of-study visit. Subjects' GICS, DSFS, and mROMP drooling scores also improved at all assessments. mROMP speech and swallowing scores remained stable. The most common treatment-related AEs during the extension period were dry mouth (4.4% and 11.1%) and dysphagia (1.5% and 4.2%). CONCLUSIONS: Data support long-term efficacy and safety of repeated incobotulinumtoxinA treatment for sialorrhea, with no additional safety concerns reported over 64 weeks.

SIAXI: Placebo-controlled, randomized, double-blind study of incobotulinumtoxinA for sialorrhea.

OBJECTIVE: This pivotal phase III study, SIAXI, investigated the efficacy and safety of incobotulinumtoxinA for the treatment of chronic sialorrhea due to Parkinson disease (PD), atypical parkinsonism, stroke, or traumatic brain injury (TBI). METHODS: Adult patients with PD (70.7%), atypical parkinsonism (8.7%), stroke (19.0%), or TBI (2.7%) were randomized (2:2:1) to double-blind treatment with placebo (n = 36), or total doses of incobotulinumtoxinA 75 U (n = 74) or 100 U (n = 74), in a single treatment cycle. The coprimary endpoints were change in unstimulated salivary flow rate from baseline to week 4, and patients' Global Impression of Change Scale score at week 4. Adverse events were recorded throughout. RESULTS: A total of 184 patients were randomized. Both incobotulinumtoxinA dose groups showed reductions in mean unstimulated salivary flow rate at week 4, with a significant difference vs placebo in the incobotulinumtoxinA 100 U group (p = 0.004). Patients' Global Impression of Change Scale scores also improved at week 4, with a significant difference vs placebo in the incobotulinumtoxinA 100 U group (p = 0.002). A lasting effect was observed at week 16 post injection. The most frequent treatment-related adverse events in the incobotulinumtoxinA 75 U and 100 U groups were dry mouth (5.4% and 2.7% of patients) and dysphagia (2.7% and 0.0% of patients). CONCLUSIONS: IncobotulinumtoxinA 100 U is an effective and well-tolerated treatment of chronic sialorrhea in adults. CLINICALTRIALSGOV IDENTIFIER: NCT02091739. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that incobotulinumtoxinA reduces salivary flow rates in patients with chronic sialorrhea due to PD, atypical parkinsonism, stroke, or TBI.

Towards unambiguous reporting of complications related to deep brain stimulation surgery: A retrospective single-center analysis and systematic review of the literature.

BACKGROUND AND OBJECTIVE: To determine rates of adverse events (AEs) related to deep brain stimulation (DBS) surgery or implanted devices from a large series from a single institution. Sound comparisons with the literature require the definition of unambiguous categories, since there is no consensus on the reporting of such AEs. PATIENTS AND METHODS: 123 consecutive patients (median age 63 yrs; female 45.5%) treated with DBS in the subthalamic nucleus (78 patients), ventrolateral thalamus (24), internal pallidum (20), and centre médian-parafascicular nucleus (1) were analyzed retrospectively. Both mean and median follow-up time was 4.7 years (578 patient-years). AEs were assessed according to three unambiguous categories: (i) hemorrhages including other intracranial complications because these might lead to neurological deficits or death, (ii) infections and similar AEs necessitating the explantation of hardware components as this results in the interruption of DBS therapy, and (iii) lead revisions for various reasons since this involves an additional intracranial procedure. For a systematic review of the literature AE rates were calculated based on primary data presented in 103 publications. Heterogeneity between studies was assessed with the I2 statistic and analyzed further by a random effects meta-regression. Publication bias was analyzed with funnel plots. RESULTS: Surgery- or hardware-related AEs (23) affected 18 of 123 patients (14.6%) and resolved without permanent sequelae in all instances. In 2 patients (1.6%), small hemorrhages in the striatum were associated with transient neurological deficits. In 4 patients (3.3%; 0.7% per patient-year) impulse generators were removed due to infection. In 2 patients electrodes were revised (1.6%; 0.3% per patient-year). There was no lead migration or surgical revision because of lead misplacement. Age was not statistically significant different (p>0.05) between patients affected by AEs or not. AE rates did not decline over time and similar incidences were found among all patients (423) implanted with DBS systems at our institution until December 2016. A systematic literature review revealed that exact AE rates could not be determined from many studies, which could not be attributed to study designs. Average rates for intracranial complications were 3.8% among studies (per-study analysis) and 3.4% for pooled analysis of patients from different studies (per-patient analysis). Annual hardware removal rates were 3.6 and 2.4% for per-study and per-patient analysis, respectively, and lead revision rates were 4.1 and 2.6%, respectively. There was significant heterogeneity between studies (I2 ranged between 77% and 91% for the three categories; p< 0.0001). For hardware removal heterogeneity (I2 = 87.4%) was reduced by taking study size (p< 0.0001) and publication year (p< 0.01) into account, although a significant degree of heterogeneity remained (I2 = 80.0%; p< 0.0001). Based on comparisons with health care-related databases there appears to be publication bias with lower rates for hardware-related AEs in published patient cohorts. CONCLUSIONS: The proposed categories are suited for an unequivocal assessment of AEs even in a retrospective manner and useful for benchmarking. AE rates in the present cohorts from our institution compare favorable with the literature.

Nonmotor fluctuations: phenotypes, pathophysiology, management, and open issues.

Parkinson's disease (PD) is a neurodegenerative multisystem disorder characterized by progressive motor symptoms such as bradykinesia, tremor and muscle rigidity. Over the course of the disease, numerous non-motor symptoms, sometimes preceding the onset of motor symptoms, significantly impair patients' quality of life. The significance of non-motor symptoms may outweigh the burden through progressive motor incapacity, especially in later stages of the disease. The advanced stage of the disease is characterized by motor complications such as fluctuations and dyskinesias induced by the long-term application of levodopa therapy. In recent years, it became evident that various non-motor symptoms such as psychiatric symptoms, fatigue and pain also show fluctuations after chronic levodopa therapy (named non-motor fluctuations or NMFs). Although NMFs have moved into the focus of interest, current national guidelines on the treatment of PD may refer to non-motor symptoms and their management, but do not mention NMF, and do not contain recommendations on their management. The present article summarizes major issues related to NMF including clinical phenomenology and pathophysiology, and outlines a number of open issues and topics for future research.

Adverse events in deep brain stimulation: A retrospective long-term analysis of neurological, psychiatric and other occurrences.

BACKGROUND AND OBJECTIVE: The extent to which deep brain stimulation (DBS) can improve quality of life may be perceived as a permanent trade-off between neurological improvements and complications of therapy, comorbidities, and disease progression. PATIENTS AND METHODS: We retrospectively investigated 123 consecutive and non-preselected patients. Indications for DBS surgery were Parkinson's disease (82), dystonia (18), tremor of different etiology (21), Huntington's disease (1) and Gilles de la Tourette syndrome (1). AEs were defined as any untoward clinical occurrence, sign or patient complaint or unintended disease if related or unrelated to the surgical procedures, implanted devices or ongoing DBS therapy. RESULTS: Over a mean/median follow-up period of 4.7 years (578 patient-years) 433 AEs were recorded in 106 of 123 patients (86.2%). There was no mortality or persistent morbidity from the surgical procedure. All serious adverse events (SAEs) that occurred within 4 weeks of surgery were reversible. Neurological AEs (193 in 85 patients) and psychiatric AEs (78 in 48 patients) were documented most frequently. AEs in 4 patients (suicide under GPI stimulation, weight gain >20 kg, impairment of gait and speech, cognitive decline >2 years following surgery) were severe or worse, at least possibly related to DBS and non reversible. In PD 23.1% of the STN-stimulated patients experienced non-reversible (or unknown reversibility) AEs that were at least possibly related to DBS in the form of impaired speech or gait, depression, weight gain, cognitive disturbances or urinary incontinence (severity was mild or moderate in 15 of 18 patients). Age and Hoehn&Yahr stage of STN-simulated PD patients, but not preoperative motor impairment or response to levodopa, showed a weak correlation (r = 0.24 and 0.22, respectively) with the number of AEs. CONCLUSIONS: DBS-related AEs that were severe or worse and non-reversible were only observed in PD (4 of 82 patients; 4.9%), but not in other diseases. PD patients exhibited a significant risk for non-severe AEs most of which also represented preexisting and progressive axial and non-motor symptoms of PD. Mild gait and/or speech disturbances were rather frequent complaints under VIM stimulation. GPI stimulation for dystonia could be applied with negligible DBS-related side effects.

Patients' perception of Parkinson's disease-associated pain following initiation of rotigotine: a multicenter non-interventional study.

OBJECTIVES: To evaluate Parkinson's disease (PD)-associated pain as perceived by the patients (subjective characterization), and how this may change following initiation of rotigotine transdermal patch. METHODS: SP1058 was a non-interventional study conducted in routine clinical practice in Germany and Austria in patients experiencing PD-associated pain (per the physician's assessment). Data were collected at baseline (ie, before rotigotine initiation) and at a routine visit after ≥25 days (-3 days allowed) of treatment on a maintenance dose of rotigotine (end of study [EoS]). Pain perception was assessed using the 12-item Pain Description List of the validated German Pain Questionnaire (each item ranked 0 = 'not true' to 3 = 'very true'). Primary effectiveness variable: change from baseline to EoS in the sum score of the 4 'affective dimension' items of the Pain Description List. Secondary effectiveness variables: change from baseline to EoS in Unified Parkinson's Disease Rating Scale (UPDRS) II, III, and II+III scores, and Parkinson's Disease Questionnaire (PDQ-8) total score (PD-related quality-of-life). Other variables included scores of the eight 'sensory dimension' items of the Pain Description List. RESULTS: Of 93 enrolled patients (mean [SD] age: 71.1 [9.0] years; male: 48 [52%]), 77 (83%) completed the study, and 70 comprised the full analysis set. The mean (SD) change from baseline in the sum score of the four 'affective dimension' items was -1.3 (2.8) indicating a numerical improvement (baseline: 3.9 [3.4]). In the 'sensory dimension', pain was mostly perceived as 'pulling' at baseline (49/70 [70%]); 'largely true'/'very true'). Numerical improvements were observed in all UPDRS scores (mean [SD] change in UPDRS II+III: -5.3 [10.5]; baseline: 36.0 [15.9]), and in PDQ-8 total score (-2.0 [4.8]; baseline: 10.7 [5.9]). Adverse drug reactions were consistent with dopaminergic stimulation and transdermal administration. CONCLUSION: The perception of the 'affective dimension' of PD-associated pain numerically improved in patients treated with rotigotine. ClinicalTrials.gov identifier: NCT01606670; https://clinicaltrials.gov/ct2/show/NCT01606670?term=NCT01606670&rank=1.

Impact of Deep Brain Stimulation on Daily Routine Driving Practice in Patients with Parkinson's Disease.

Objective. To determine the influence of deep brain stimulation (DBS) on daily routine driving behavior in Parkinson's disease (PD) patients. Methods. A cross-sectional questionnaire survey was done in 121 DBS-PD patients. The influences of patient characteristics and DBS on current driving and driving at time of surgery and the predictive value of the preoperative levodopa-test on postoperative driving were evaluated. Results. 50% of 110 driving-license holders currently drove. 63.0% rated themselves as safe drivers, 39.4% reported improvement, and 10.9% noted deterioration in driving after DBS surgery. Inactive drivers had quit driving mainly due to disease burden (90.9%). Active drivers were younger, more often males, and less impaired according to H&Y and MMSE, had surgery more recently, and reported more often overall benefit from DBS. H&Y "on" and UPDRS III "off" scores at time of surgery were lower in pre- and postoperative active than in inactive drivers. Tremor and akinesia were less frequent reasons to quit driving after than before DBS surgery. Postoperatively, 22.7% (10/44) of patients restarted and 10.6% (7/66) of patients discontinued driving, independently of H&Y stage. The preoperative levodopa-test was not predictive for the postoperative driving outcome. Conclusion. 50% of PD patients with DBS drive. DBS surgery changes daily routine driving behavior.

Effect of neurostimulation on camptocormia in Parkinson's disease depends on symptom duration.

Although some reports on neurostimulation are positive, no effective treatment method for camptocormia in Parkinson's disease (PD) is known to date. We aim to identify prognostic factors for a beneficial DBS effect on camptocormia. In an observational cohort study, we investigated 25 idiopathic PD patients, who suffered additionally from camptocormia, and underwent bilateral neurostimulation of the subthalamic nucleus (STN) to improve classical PD symptoms. Using an established questionnaire, we examined deep brain stimulation (DBS) effects on camptocormia in addition to general neurostimulation effects. A beneficial neurostimulation effect on camptocormia was defined as an improvement in the bending angle of a least 50%. In 13 patients, the bending angle of camptocormia improved, in 12 patients it did not. A multifactorial analysis revealed a short duration between onset of camptocormia and start of neurostimulation to be the relevant factor for outcome. All patients with duration of camptocormia up to 1.5 years showed a beneficial effect; patients between 1.5 and ∼3 years showed mixed results, but none with a duration of more than 40 months improved except for 1 patient whose camptocormia was levodopa responsive. The bending angle was not a prognostic factor. Our data indicate that the main prognostic factor for a beneficial DBS effect on camptocormia is its short duration. As an explanation, we suggest that neurostimulation may improve camptocormia only as long as muscle pathology is limited. Our findings may help to elucidate the mode of action of neurostimulation. A prospective study is necessary.

Implementing conventional Zamorano Dujovny frames versus individually manufactured microTargeting platforms--a comparative study on deep brain stimulation in Parkinson patients.

BACKGROUND AND OBJECTIVES: Individually manufactured microTargeting™ platforms (MT) provide a novel generation of stereotactic systems based on preoperatively implanted bone markers and screws. The feasibility and reliability of these frames were evaluated for bilateral deep brain stimulation (DBS) in patients with idiopathic Parkinson's disease (IPD). Surgical and clinical results were compared to conventional Zamorano Dujovny frames (ZD) in this prospective study. MATERIALS AND METHODS: Twenty-six IPD patients undergoing surgery for DBS were divided into 2 groups. In group I, electrode implantation was accomplished using conventional ZD. Group II underwent electrode implantation using MT. Microrecording and macrostimulation were performed and surgery time was measured. The clinical outcome was determined using the Unified Parkinson's Disease Rating Scale Part III (UPDRS III) and L-dopa-equivalent doses for a 12-month follow-up postoperatively. RESULTS: Clinical evaluation confirmed comparable outcomes for both targeting procedures and electrode positioning. Surgical time was lower in group II than in group I. Significant improvements were determined for both groups in UPDRS III and L-dopa-equivalent dose. CONCLUSIONS: Both systems allow for reliable and safe neurosurgical procedures, yielding comparable clinical results. MT improved handling and automatic adjustment of frame coordinates. Surgery time was reduced markedly compared to conventional frames.

STN stimulation in general anaesthesia: evidence beyond 'evidence-based medicine'.

Awake surgery is regarded mandatory for optimal electrode implantation into the subthalamic nucleus (STN) for deep brain stimulation (DBS) in Parkinson's disease (PD). However, this is questionable since general anaesthesia (GA) does not preclude intraoperative microrecordings and clinical evaluation of, for example, current spread to the corticospinal tract. In addition, even in the awake state, clinical testing is not without limitations. We report on intra- and postoperative findings in 11 patients suffering from advanced PD who were operated under GA (propofol/remifentanil). The activity of STN neurons under GA was characterized by excessive burst discharges that differed fundamentally from the irregular tonic patterns observed in the STN of awake patients. In all patients, we obtained improved motor symptoms and reduced levodopa-induced dyskinesias and motor fluctuations, which was associated with a reduction in the levodopa equivalent daily dose. Therapeutic DBS was not limited by current spread to the corticospinal tract in any of the patients. The trajectories chosen for electrode implantation in GA compared well to awake surgery. Our results indicate that STN surgery in GA can be performed in a safe manner. It can be offered to anxious patients, and represents a viable option when awake surgery bears a risk for the patient.

Switch from selegiline to rasagiline is beneficial in patients with Parkinson's disease.

The objective of this study is to demonstrate that application of rasagiline instead of selegiline with concomitant determination of L-amphetamine and L-methamphetamine in plasma is safe and well tolerated and influences sleep, mood, and motor behavior in patients with Parkinson's disease on a stable drug therapy. 30 patients, who took 7.5 mg selegiline daily for at least 3 months, were switched to 1 mg rasagiline. Then they were followed over an interval of 4 months. The remaining drug therapy remained stable. This changeover was safe and well tolerated. L-Amphetamine and L-methamphetamine only appeared during selegiline treatment. Motor behavior, motor complications, mood and sleep improved during rasagiline administration. Amphetamine-like derivatives of selegiline could contribute to sleep disturbances, which may be involved in worsening of mood. Motor behavior and motor complications probably became better due to the additional glutamate receptor antagonizing properties of rasagiline in this open label study.

Monoamine transporter availability in Parkinson's disease patients with or without depression.

PURPOSE: Depression is a common symptom in patients suffering from Parkinson's disease (PD) and markedly reduces their quality of life. As post-mortem studies have shown, its presence may reflect extensive cell loss in the midbrain and brainstem with imbalances in monoaminergic neurotransmitters. However, in vivo evidence of specific monoaminergic deficits in depressed PD patients is still sparse. Therefore, we studied PD patients with depression (PD+D) and without depression (PD-D) using high-resolution single-photon emission computed tomography (SPECT) and the monoamine transporter marker [(123)I]FP-CIT. METHODS: A magnetic resonance imaging-based region-of-interest analysis was applied to quantify the specific-to-nondisplaceable [(123)I]FP-CIT binding coefficient V(3)'' in the striatum, thalamus and midbrain/brainstem regions. RESULTS: PD+D patients had significantly lower V(3)'' compared with PD-D patients in the striatum (p<0.001), thalamus (p=0.002), and midbrain/brainstem (p=0.025). Only PD+D patients without selective serotonin reuptake inhibitor (SSRI) treatment showed lower thalamic and midbrain V(3)'' than controls (p<0.001, p=0.029). In a small sub-group of SSRI-treated PD+D patients neither thalamic V(3)'' nor midbrain/brainstem V(3)'' differed from those in PD-D patients (p=0.168, p=0.201) or controls (p=0.384, p=0.318). CONCLUSION: Our data indicate that depression in PD is associated with a more pronounced loss of striatal dopamine transporter availability that is most likely secondary to increased dopaminergic degeneration. In addition, depressed PD patients have a lower availability of midbrain/brainstem monoamine transporters than nondepressed PD patients. These findings provide in vivo evidence in support of the known post-mortem data demonstrating more extensive nerve cell loss in PD with depression and indicate that SPECT imaging can help to identify pathophysiological changes underlying nonmotor symptoms in this common movement disorder.

Kinetic analyses of [123I]IBZM SPECT for quantification of striatal dopamine D2 receptor binding: a critical evaluation of the single-scan approach.

BACKGROUND: Dopamine-D2 receptor imaging with single-photon emission computed tomography (SPECT) and [(123)I]IBZM is of great interest for basic and applied neurosciences. However, the use of kinetic analyses for quantification of dynamic [(123)I]IBZM SPECT and the validity of the commonly employed single-scan pseudo-equilibrium analysis (PsEA) have not been appropriately investigated. The present study addresses these shortcomings. METHODS: Ten movement disorder patients underwent dynamic SPECT (142 min) after single-bolus [(123)I]IBZM injection. Kinetic analyses comprise: simplified reference tissue model (SRTM), multi-linear reference tissue model (MRTM), their two-parameter versions (SRTM2/MRTM2) and non-invasive graphical analysis (NIGA). Simplified single-scan analyses were performed at peak time of specific binding (peak-equilibrium analysis, PEA) and during pseudo-equilibrium (PsEA). RESULTS: SRTM and MRTM are compromised by the high noise level of dynamic SPECT. SRTM2 and MRTM2 yielded reliable binding potential estimates that agreed excellently (mean difference=-0.1+/-1.0%, R(2)>0.99). Concordance between SRTM/MRTM and SRTM2/MRTM2 was high in cases in which SRTM/MRTM provided reliable results (SRTM2 or MRTM2 vs. SRTM: 3.7+/-5.0%, R(2)=0.88). NIGA was affected by a negative bias (-9.1+/-6.3%, R(2)=0.75; MRTM2 as reference) or high variability (-1.2+/-7.4%, R(2)=0.71) for analyses without and with inclusion of the k(2)'-term, respectively. PsEA showed a positive bias and low correlation in comparison with SRTM2/MRTM2 (7.6+/-10.8%, R(2)=0.59), which was considerably improved for PEA (-2.7+/-7.6%, R(2)=0.72). MRTM2 provided parametric images with minimal bias suited for voxel-wise statistical analyses. CONCLUSIONS: MRTM2 and SRTM2 can be reliably applied to dynamic [(123)I]IBZM SPECT. PEA is a suitable method for clinical routine, while our results discourage the use of PsEA (current clinical standard).

Effects of subthalamic nucleus stimulation on striatal dopaminergic transmission in patients with Parkinson's disease within one-year follow-up.

The mechanisms by which deep brain stimulation (DBS) of the subthalamic nucleus (STN) leads to clinical benefit in Parkinson's disease (PD), especially with regard to dopaminergic transmission, remain unclear. Therefore, the objective of our study was to evaluate alterations of synaptic dopaminergic signaling following bilateral STN-DBS in advanced PD within a one-year follow-up. We used [(123)I]FP-CIT single-photon emission computed tomography (SPECT) to measure dopamine transporter (DAT) availability and [(123)I]IBZM SPECT to assess dopamine D(2) receptor (D2R) availability (stimulator ON condition).Patients (n=18) showed a tendency towards a better suppression of symptoms after STN-DBS (Unified Parkinson's Disease Rating Scale motor score with medication decreased from 24.1+/-16.1 to 15.4+/-7.45; p=0. 002) while medication was strongly reduced (61% reduction of levodopa equivalent units; p<0. 0001). No changes of striatal [(123)I]FP-CIT binding and an increase of [(123)I]IBZM binding up to 16% (p<0. 05) between pre-surgery and follow-up investigations were noticed. These data show that clinical improvement and reduction of dopaminergic drugs in patients with advanced PD undergoing bilateral STN-DBS are paralleled by stable DAT and recovery of striatal D2R availability 12 months after surgery.

High-dose treatment with pergolide in Parkinson's disease patients with motor fluctuations and dyskinesias.

Motor complications arising after long-term treatment with levodopa remain one of the main challenges in the treatment of patients with Parkinson's disease (PD). Monotherapy with dopamine agonists may delay the onset of motor complications or reduce their severity when added to levodopa treatment. Here, we retrospectively analyzed data from 62 patients with advanced PD who presented with moderate to severe response fluctuations in whom we increased the dose of oral treatment with pergolide beyond 4.5mg daily. Patients had been treated with levodopa for 10.7+/-4.8 years. Pergolide was increased to 8.2+/-4.3 mg per day over a median titration period of 13.5 weeks. Mean daily dose of levodopa prior to pergolide high-dose treatment was 733+/-468 mg and decreased to 348+/-186 mg after pergolide titration. The duration of OFF times decreased from 7.3+/-3.8 to 1.7+/-0.9 h per day (p < 0.001) measured by patients' diaries. Dyskinesias, present for 5.0+/-3.3 h per day at baseline, were reduced to 1.4+/-0.8 h per day (p < 0.001) and the total daily duration of motor fluctuations (off-time duration plus dyskinesia duration) decreased from 10.5+/-7.0 to 2.8+/-2.2 h (p < 0.001). There was a significant improvement in parkinsonian symptoms (baseline to endpoint reduction of UPDRS III from a median of 36 to 8; p < 0.001). To reduce gastrointestinal side effects 23 patients required concomitant treatment with domperidone. Seven patients developed hallucinations during the titration period, six patients required treatment with clozapine. Our data indicate that increasing the dose of pergolide above 5mg per day can dramatically reduce the need for levodopa, motor fluctuations and severity of clinical symptoms. Controlled trials are needed to further substantiate the efficacy and safety of this treatment strategy.